If you want proper litho printed...minimum 1000, these people do good work. Postcards are quite expensive, but excellent quality (£110 + VAT per 1000)If you look at 300gsm flyers you will get a good price (£42.90 per 1000, flyers are zero rated for VAT too)

Like any dealer he was watching for the card that is so high and wild he'll never need to deal another...